Как в picasso открывать картинки на всю область экрана?

public class GridViewAdapter extends BaseAdapter {
    private Context context;
    public String[] items = {
            "http://topmemas.top/img/img/1517414160.jpg",
            "http://topmemas.top/img/img/1518633309.jpg",
            "http://topmemas.top/img/img/1517859960.jpg",
           };

    public GridViewAdapter(Context context){
        this.context=context;

    }
    @Override
    public int getCount() {
        return items.length;
    }
    @Override
    public Object getItem(int position) {
        return items[position];
    }
    @Override
    public long getItemId(int position) {
        return position;
    }
    @Override
    public View getView(int position, View convertview, ViewGroup parent) {
        ImageView img;
        if (convertview == null){
            img = new ImageView(context);
            convertview = img;
            img.setPadding(10,10,10,10);

        }else {
            img =(ImageView)convertview;
        }

       Picasso.with(context).load(items[position]).placeholder(R.drawable.image)
                .resize(320,320)
                .into(img);
          return convertview;
    }
}

public class FullImageActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_full_image);

        Intent i =getIntent();
        int position=i.getExtras().getInt("id");
        GridViewAdapter adapter = new GridViewAdapter(this);
        ImageView img=(ImageView)findViewById(R.id.imageViewfull);

        img.setImageResource(adapter.items[position]);
    }
Error:(23, 43) error: incompatible types: String cannot be converted to int

public class FragmentMems extends android.support.v4.app.Fragment {
    private GridView gridView;

    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_user_mems, container, false);
        gridView = (GridView) rootView.findViewById(R.id.gridview);
        gridView.setAdapter(new GridViewAdapter(getContext()));

        gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) {
                Intent i =new Intent(getContext(),FullImageActivity.class);
                i.putExtra("id",position);
                startActivity(i);

            }
        });   return rootView;
    }
}